Library Folder ClasspathContainer update site.
  Help -> Software Updates -> Find and Install
    (In Install/Update dialog)  select 'Search for new features to install' radio button
    (In Install dialog)         click  'New Remote Site' button
    (In New Update Site dialog) input

  (In properties dialog for your project)
    - select 'Java Build Path'
    - select 'Libraries' tab
    - click  'Add Library' button 
  (In Add Library dialog)
    - choose 'Library Container'
    - choose the folder

To obtain source codes, visit